A 22-year-old Penacook man befriended nearly 2,000 teenage girls from around the world on Facebook in an attempt to solicit nude pictures from them and received hundreds of photos in exchange, including several explicit ones from a teenager living in the Manchester area, the police said.

Jeremy Stinson, a 2009 graduate of Merrimack Valley High School, is facing nine charges of possessing child sexual abuse images. The indictments against him come more than two years into an investigation by the Concord police that officials say began after a 15-year-old girl in the United Kingdom told the police there that Stinson had approached her online.

Officials in the U.K. contacted Facebook, which conducted its own investigation and notified the New Hampshire Internet Crimes Against Children Task Force of its findings in spring 2011.

Facebook investigators, according to a search warrant filed in Concord’s district court, found that Stinson created four separate accounts pretending to be a 15-year-old boy named Cole Armstrong. A Concord detective later tied all of those accounts to an IP address registered to Stinson at Keene State College, where he lived on campus during the 2010-11 school year, according to the affidavit.

The police said all four of the accounts were created during that time frame, and Stinson also logged into his personal Facebook account from the same IP address, which helped detectives connect him to the fake Cole Armstrong profiles.

Stinson was forced to create several profiles, using slightly different email addresses for each, when Facebook shut down his previous accounts, according to Concord police Lt. Timothy O’Malley.

“He bounced between Hotmail, Yahoo, Hotmail, Yahoo and then slightly changed the (email) address by one digit because they kept closing him down,” he said.

O’Malley said the 2,000 girls Stinson added as friends were between 13 and 17.

Stinson sent messages to about 1,000 of those girls, attempting to become their friend by telling them they were attractive, the police said. With many, the conversation then turned sexual and Stinson would ask them to send him pictures or chat with him online “for the purposes of sexual gratification,” according to the affidavit.

At that point, many of the girls stopped talking to him, O’Malley said. But some obliged.

“His net was cast wide,” O’Malley said.

Stinson is also accused of sending nude pictures of himself, including some which show his face, to many of the teens. While the police say Stinson primarily used the Cole Armstrong accounts, Facebook investigators also said that in March 2011 he was actively grooming a 14-year-old girl from his own profile.

The police executed a search warrant at the Village Street home where Stinson lives with his family in November 2011, seizing two laptops, a computer tower and an external hard drive, according to court documents.

O’Malley said a detective found hundreds of nude pictures on the computer but he was unable to say how many girls were included in that group. He said, though, that not all of those pictures depicted the “sexually explicit conduct” involving an individual known to be a minor necessary to charge Stinson with possession of child sexual abuse images.

The 15-year-old girl who lives near Manchester sent Stinson about 40 photos, four of which fit that category, the police said.

Those four plus five other pictures of different girls the police say they could determine were teenagers resulted in the nines Class A felonies Stinson was indicted on earlier this month by a Merrimack County grand jury.

The police believe Stinson was also in contact with another local teenager, a 14-year-old girl who lives in the Lakes Region. O’Malley said conversations between Stinson and the girl found on his computer indicate the two exchanged explicit photos.

But pictures of the girl were not found on his computer, and the girl’s family has not cooperated with investigators, which has kept the police from finding out whether Stinson sent nude pictures of himself to her, O’Malley said.

Stinson did not return a message left on his cell phone Thursday. He will be arraigned July 10 at Merrimack County Superior Court.

O’Malley said that while the police don’t know if Stinson has continued to use computers since detectives seized his in November 2011, “he’s aware that we’re watching him.”

He said several factors caused the investigation to carry on for more than two years, the most cumbersome being completing forensic analyses on the four computers and hard drives taken from Stinson’s home. O’Malley said a detective devoted about 40 hours to each device.

Many of the photos uncovered were then sent to the National Center for Missing and Exploited Children, which took about three months comparing them with their own database of victims known to have appeared in child sexual abuse images or videos. O’Malley said the detective also went before a Merrimack County grand jury several times to get subpoenas for the various email clients Stinson used to create his Facebook accounts.